ISSN 1783-3426 THE MASSIVE STAR NEWSLETTER formerly known as the hot star newsletter * No. 151 2016 January-February Editors: Philippe Eenens (University of Guanajuato) [email protected] Raphael Hirschi (Keele University) http://www.astroscu.unam.mx/massive_stars CONTENTS OF THIS NEWSLETTER: News Obituaries Paul Kunasz and David Hummer Fizeau exchange visitors program Abstracts of 18 accepted papers Classical Oe Stars in the Field of the Small Magellanic Cloud An Apparent Precessing Helical Outflow from a Massive Evolved Star: Evidence for Binary Interaction A Comprehensive Comparative Test of Seven Widely-Used Spectral Synthesis Models Against Multi- Band Photometry of Young Massive Star Clusters Modeling X-ray emission line profiles from massive star winds – A review Long-Wavelength, Free-Free Spectral Energy Distributions from Porous Stellar Winds The Runaways and Isolated O-Type Star Spectroscopic Survey of the SMC (RIOTS4) Eta Carinae's Thermal X-ray Tail Measured with XMM-Newton and NuSTAR Stellar modelling of Spica, a high-mass spectroscopic binary with a beta Cep variable primary component Observational signatures of past mass-exchange episodes in massive binaries: The case of HD149404 The Galactic O-Star Spectroscopic Survey (GOSSS). III. 142 additional O-type systems Probing the Dragonfish star-forming complex: the ionizing population of the young massive cluster Mercer 30 Short-term variability and mass loss in Be stars I. BRITE satellite photometry of eta and mu Centauri Luminous blue variables: An imaging perspective on their binarity and near environment OB stars at the lowest Local Group metallicity. GTC-OSIRIS observations of Sextans A Herschel observations of the nebula M1-67 around the Wolf-Rayet star WR 124 The Massive Stellar Population of W49: A Spectroscopic Survey Line-driven ablation of circumstellar disks: I. Optically thin decretion disks of classical Oe/Be stars Analysis of the WN star WR 102c, its WR nebula, and the associated cluster of massive stars in the Sickle Nebula Jobs Two Faculty Positions in Astrophysics at Instituto de Astrofisica de Atacama, Copiapo (Chile) 11 postdoc positions at Instituto de Astrofisica de Canarias Postdoctoral position on Gaia and massive stars Meetings Bridging the gap: from massive stars to supernovae Frontiers of massive-star evolution and core-collapse supernovae Supernova Remnants: An Odyssey In Space After Stellar Death Potsdam Astrophysical Summer School "Quantitative Spectroscopy in Astrophysics" News Obituaries Paul Kunasz and David Hummer Dear colleagues, some of you might already have heard the sad news that David Hummer has passed away recently. I was just informed that also Paul Kunasz has died, already in August 2015. Together with Dimitri Mihalas, we thus lost, during the last year, three of the world-leading pioneers and experts on radiative transfer, stellar atmospheres and may more topics. As an example, you might remember the most influential series of papers on comoving frame transfer, published by Mihalas, Kunasz & Hummer in the 1970ies. I am sure that everybody will miss them. An obituary for Paul Kunasz can be found on http://www.legacy.com/obituaries/dailycamera/obituary.aspx?pid=175559352 and an obituary for David Hummer on http://www.dailycamera.com/features/ci_29348396/friends-peers-raise-final-pint-david-hummer-co Those of you who are not aware of David's other 'profession', as a founder of one of the first micro- breweries in the USA, might be particularly interested in the latter article. Jo Puls Weblink: Email: [email protected] Back to contents Fizeau exchange visitors program: call for applications (Now closed) J. Hron & L. Misoni European Interferometry Initiative The Fizeau exchange visitors program in optical interferometry funds (travel and accommodation) visits of researchers to an institute of his/her choice (within the European Community) to perform collaborative work and training on one of the active topics of the European Interferometry Initiative. The visits will typically last for one month, and strengthen the network of astronomers engaged in technical, scientific and training work on optical/infrared interferometry. The program is open for all levels of astronomers (Ph.D. students to tenured staff), non-EU based missions will only be funded if considered essential by the Fizeau Committee. Applicants are strongly encouraged to seek also partial support from their home or host institutions. The deadline for applications is March 15. Fellowships can be awarded for missions starting in May 2016. Further informations and application forms can be found at www.european-interferometry.eu The program is funded by OPTICON/FP7. Please distribute this message also to potentially interested colleagues outside of your community! Looking forward to your applications, Josef Hron & Laszlo Mosoni (for the European Interferometry Initiative) Reference: Deadline March 15 Status: Other Weblink: www.european-interferometry.eu Comments: Please circulate not later than March 1 Email: [email protected] Back to contents PAPERS Abstracts of 18 accepted papers Classical Oe Stars in the Field of the Small Magellanic Cloud Jesse B. Golden-Marx (1), M. S. Oey (1), J. B. Lamb (2), Andrew S. Graus (3), Aaron S. White (1) ((1) University of Michigan, (2) Nassau Community College, (3) University of California, Irvine) We present 29±1 classical Oe stars from RIOTS4, a spatially complete, spectroscopic survey of Small Magellanic Cloud (SMC) field OB stars. The two earliest are O6e stars, and four are earlier than any Milky Way (MW) Oe stars. We also find ten Ope stars, showing He~\textsc{i} infill and/or emission; five appear to be at least as hot as ∼O7.5e stars. The hottest, star 77616, shows He~\textsc{ii} disk emission, suggesting that even the hottest O stars can form decretion disks, and offers observational support for theoretical predictions that the hottest, fastest rotators can generate He+-ionizing atmospheres. Our data also demonstrate that Ope stars correspond to Oe stars earlier than O7.5e with strong disk emission. We find that in the SMC, Oe stars extend to earlier spectral types than in the MW, and our SMC Oe/O frequency, 0.26±0.04, is much greater than the MW value, 0.03±0.01. These results are consistent with angular momentum transport by stronger winds suppressing decretion disk formation at higher metallicity. In addition, our SMC field Oe star frequency is indistinguishable from that for clusters, which is consistent with the similarity between rotation rates in these environments, and contrary to the pattern for MW rotation rates. Thus, our findings strongly support the viscous decretion disk model and confirm that Oe stars are the high-mass extension of the Be phenomenon. Additionally, we find that Fe~\textsc{ii} emission occurs among Oe stars later than O7.5e with massive disks, and we revise a photometric criterion for identifying Oe stars to J−[3.6]≥0.1. Reference: Accepted for publication in ApJ Status: Manuscript has been accepted Weblink: http://arxiv.org/abs/1601.03405 Email: [email protected] Back to contents An Apparent Precessing Helical Outflow from a Massive Evolved Star: Evidence for Binary Interaction Ryan M. Lau$^{1,2}$, Matthew J. Hankins$^{1}$, Terry L. Herter$^{1}$, Mark R. Morris$^{3}$, Elisabeth A. C. Mills$^{4}$, Michael E. Ressler$^{2}$ 1 - Cornell Astronomy Department; 2 - Caltech/JPL; 3 - Department of Physics and Astronomy, UCLA; 4 - National Radio Astronomy Observatory Massive, evolved stars play a crucial role in the metal-enrichment, dust budget, and energetics of the interstellar medium; however, the details of their evolution are uncertain because of their rarity and short lifetimes before exploding as supernovae. Discrepancies between theoretical predictions from single-star evolutionary models and observations of massive stars have evoked a shifting paradigm that implicates the importance of binary interaction. We present mid- to far-infrared observations from the Stratospheric Observatory for Infrared Astronomy (SOFIA) of a conical ``helix'' of warm dust ($\sim180$ K) that appears to extend from the Wolf-Rayet star WR102c. Our interpretation of the helix is a precessing, collimated outflow that emerged from WR102c during a previous evolutionary phase as a rapidly rotating luminous blue variable. We attribute the precession of WR102c to gravitational interactions with an unseen compact binary companion whose orbital period can be constrained to $800\,\mathrm{d} < P < 1400$ d from the inferred precession period, $\tau_p \sim 1.4\times 10^4$ yr, and limits imposed on the stellar and orbital parameters of the system. Our results concur with the range of orbital periods ($P\lesssim 1500$ d) where spin-up via mass exchange is expected to occur for massive binary systems. Reference: arXiv:1512.07639 Status: Manuscript has been accepted Weblink: http://arxiv.org/abs/1512.07639 Comments: Revised version to be updated Tuesday 1/19/2016 Email: [email protected] Back to contents A Comprehensive Comparative Test of Seven Widely-Used Spectral Synthesis Models Against Multi-Band Photometry of Young Massive Star Clusters A. Wofford, S. Charlot, G. Bruzual, J. J. Eldridge, D. Calzetti, A. Adamo, M. Cignoni, S. E. de Mink, D. A. Gouliermis, K. Grasha, E. K. Grebel, J. Lee, G. Ostlin, L. J. Smith, L. Ubeda, E. Zackrisson Sorbonne Universites, UPMC-CNRS, UMR7095, Institut d’Astrophysique de Paris We test the predictions of spectral synthesis models based on seven different massive-star